Relay-operating mechanism



Feb. 25, 1930. R. c. LEAKE RELAY OPERATING MECHANISM Filed March 25, 1926 Patented Feb. 25, 1930 PTENT OFFICE RICHARD C. LEAKE, OF ROCHESTER, NEVI YORK, ASSIGNOR 'I'O GENERAL RAILWAY SIGNAL COMPANY, OF ROCHESTER, NEW YORK RELAY-OPERATING MECHANISM Application filed March 25, 1826.

This invention relates to relays and more particularly concerns a relay mechanism for use in automatic train control and signaling circuits.

In certain railway signaling and train control circuits, it is necessary to control the op-' eration of electrical devices in accordance with the variation of comparatively weak control currents. This control is often accomplished by the use of the well known polyphase type of alternating current relays, in which a. number of contacts are selectively operated by the movement of a rotor or vane which derives its torque from the magnetic fields produced by two spaced field windings carrying alternating currents which are displaced in phase relation. In this type or relay, the simultaneous energization of the field windings produces a torque which turns or rotates the movable element in one direction or the other in accordance with the phase relation of the control currents, and when either one or both of the field windings are de-energized, the contacts and other movable elements of the relay are moved to a central or neutral position by means of counter-weights, springs or other suitable devices.

Certain of the relay contacts, commonly called the neutral contacts, are closed when the relay is in the neutral position, and cer tain other contacts are opened in this position.

It often occurs in a relay of this type, that the momentum acquired by the moving elements While being driven by the spring or counter-weight means from one 01 the energized positions to the neutral position is sufiicient to carry these moving elements past the neutral position, thus causing an objectionable opening and closing or bobbing of the neutral contacts.

This undesirable bobbing of the neutral contacts may be prevented by increasing the amount of counter-weighting or strengthening the center springs used, but this method of avoiding the dilficulty is objectionable for the following reasons. The full torque which the rotor or vane is capable of delivering should be available at the end of the relay stroke, this torque acting to compress the relay contacts and thus to insure an electrical Serial No. 97,368.

contact of low resistance. In many polyphase automatic relays, and particularly in thetype employed in train control practice, springs are used to move the elements to the neutral position and as the resistance of the springs to mechanical motion increases as they are compressed, the use of powerful springs for centering the relay parts very appreciably reduces the torque available for compressing the contacts when the relay is energized and the mechanism is at the end of its stroke.

l Vith the above and other considerations in mind, it is proposed in accordance with the present invention to provide means for use in connection with polyphase alternating current relays for preventing the opening and closing or the contacts when such relay is deenergized and moved to its neutral position, and more specifically it is proposed to provide means for reducing the momentum of said moving elements of a relay of this type, and means for biasing the relay elements toward the neutral position witnout appreciably affecting the torque available for compressing the contacts when the relay is in the energized position.

Other objects, advantages and characteristic features of the invention will become apparent as the description thereof progresses.

In describing the invention in detail, reference will be made to the accompanying drawing, in which Fig. 1 is a simplified view of the relay embodying the present invention, the parts being shown in perspective and separated vertically so that their relative operation may be apparent Fig. 2 is sectional View of the rotor element of the relay shown in Fig. 1;

Fig. 3 is a sectional view of a portion of the rotor shaft; and

Fig. l is a sectional view taken along the line 4-et of Figs. 2 and 3, and viewed in the direction of the arrows.

Referring to the drawings, and particularly to Fig. 1, the relay of the present invention comprises in general a rotor element which may take any suitable form, and as shown comprises the cup shaped rotor 1, secured to a pivotally mounted shaft 2 through a lost motion connection as hereinafter described. Suitably distributed field windings are provided to produce a rotating or shifting flux through the rotor 1 in the well known manner, these field windings having been conventionally represented in the drawings at 3 and 3*. The shaft 2 carries a pinion 4 suitably secured thereto and engaging a toothed sector 5, fixed to a second shaft 6. The shafts 2 and 6 are preferably carried by suitable anti-friction bearings, represented by the pivot bearings 7 and 8.

A bracket 9 is fixedly secured to the shaft 6, this bracket being formed with two radial extensions or arms 10 and 11, carrying the pivotally mounted rollers 12 and 13 at the ends thereof. A third roller 14 is carried by a pin 15 mounted on the bracket 9 between the extensions 10 and 11 thereof, this roller being mounted to engage the bifurcated end 16 of an arm 17 fixed to the contact shaft 18. A stop spring 19 is secured to the arm 17 and extends over the end of the pin 15 in order to maintain the proper relation between the roller 14 and the bifurcated end 16 of the arm.

Any suitable type of contacts may be used in connection with the relay, and the contacts shown are of the initially tensioned type, comprising the arm 20 fixed to the contact shaft 18 and carrying the contact stri s 21 which are bent back at their ends as s own and held in tension by the retaining clips 22. The contact shaft 18 is suitably journaled in anti-friction bearings, and the arm 20 may be insulated from this shaft if desired. Stationary contacts 23 are provided, being constructed of some suitable material such as carbon. These contacts are arranged to be engaged by the contact strips 21 in the neutral or the energized positions of the relay mechanism as desired.

The particular features of the present invention comprise the lost motion connection between the rotor 1 and the shaft 2, and the centering means engaging the extensions 10 and 11 of the bracket 9.

The centering means is designated as a whole as C, and comprises a stationary base 24, rigidly secured to the relay case by the screws 25 or by other suitable means. The base 24 carries a center frame 26, made integral therewith or suitably attached thereto as desired. The base 24 is bifurcated on the opposite sides thereof and carries the pivotally mounted centering arms 27 and 28 in these bifurcations as shown. The arms 27 and 28 extend from the base 24 toward the shaft 6, and are disposed substantially parallel to each other when the relay is in the neutral or deenergized position, as shown. These centering arms are provided with enlarged portions 29 and 30 and with inwardly extending ends 31 and 32 having inclined faces 33 and 34 as shown. The center frame 26 carries a cross bar 35. riveted or otherwise suitably secured thereto, and extending loosely through openings in the enlarged portions 29 and 30 of the arms 26 and 27. The cross bar 35 is threaded at its outer ends and carries the centering sprin s 36 and 37 bearing against the outer faces 0 the arms 26 and 27 respectively.

the tension of these springs being adjustable by means of the nuts 38 and 39 engaging the extreme ends of the bar 35. The movement of the arms 27 and 28 under the pressure of the springs 36 and 37 is limited by the set screws 40 and 41 passing through threaded openings in the enlarged portions 29 and 30 and bearing against the sides of the center frame 26, lock nuts 42 being provided to maintain the screws 40 and 41 in their adjusted positions.

The arrangement of the centering device C is such that when the mechanism is in its neutral position as shown, the rollers 12 and 13 on the extensions 10 and 11 are engaged by the inner faces of the centering arms 27 and 28 with the inner sides of the inturned ends 31 and 32 engaging the rollers 12 and 13 at a point just outside. or away from the shaft 6, from a vertical plane through the pivots of the rollers 12 and 13 and parallel to the arms 27 and 28. Due to this arrangement, the initial movement of the shaft 6 and the extensions 10 and 11 from the neutral position is strongly opposed by one or the other of the centering arms 27 and 28, the inturned ends 32 and 33 of these arms having, in effect, a partial hook engagement with the rollers 12 and 13. As the shaft is moved to a point where one of the rollers, say the roller 12, engages the inclined face 34 of one of the centering arms 28, the pressure of the spring 36 is transmitted directly to the extension 10 through the centering arm 28, and as the mechanical advantage formerly obtained by the inturned end of the arm 28 no longer exists, the opposition afforded to the movement of the shaft 6 is greatly reduced at this point in its movement, and throughout the remainder of its stroke to the extreme energized position.

Considering the operation of the centering means C in a slightly different manner, when the shaft 6 is in one of its extreme energized positions, one of the rollers, say the roller 12, bears on the inclined face 34 of the inturned end 32 of the arm 28, and a given pressure is transmitted from the spring 37 through the arm 28 to the roller 12, tending to center the shaft 6 toward its neutral position. As the shaft 6 is moved toward its neutral position, the inwardly extending end 32 of the arm 28 passes around the roller 12, thus increasing the mechanical advantage of the spring 37 in moving the roller 12 together with the extension 10, the bracket 9, the shaft 6 and the remainder of the relay mechanism.

lVhen the neutral position is reached, the momentum of the moving elements oi: the relay tends to continue the motion of the shaft 6 and the bracket 9. The hook-like engagement of the inturned end 31 of the other centering arm 27 with the roller 13 prevent: the further movement or bobbing of the relay elements, and the shaft 6 is brought to a stop in the neutral position.

Referringnow more particularly to the lost motion connection etween the 2 and the rotor 1, most clearly shown in ii through 4, the rotor pro} er is of gener vertcd cup shape, having a cup po tie We made of a suitable light conducting metal such as aluminum, riveted or otherwise suitably secured to a spider or disk 4-5, preferably constructed of brass or of broniie. The disl: is provided with a downwardly extending hollow sleeve portion l6 which is screw threaded on the outside as clearly shown. The shaft 2 is provided with a flange or eX- tension 47 engaging the upper surface of the disk 4-5, and two hubs l8 and ll) engaging the inner surface of the sleeve 46 at its upper and lower ends respectively. A spring 50 is carried by the shaft 2 below the lower end of the sleeve 46, this spring being carried at its lower end by a washer 51 engaging a 1' pin 52 extending through ahole in the shaft 2. The upper end of the spring 50 bears against a. metal washer 53, which is sif bly mounted on the shaft 2 and has an integral inwardly projecting pin or lzey which engages an elongated hey-way or slot in the shaft 2 as mostclearly shown in the shaft 2, above the washer 53, are successively mounted a fiber washer 56, a metal washer 5'? having an upwardly extending integral arm 58, a fiber washer 59 and two metal washers 60 and 61, the uppermost washer 61 resting on the lower edge of the hub ll) as clearly shown. Thus the spring 50 exerts a pressure between the pin enr the shaft 2, and the hub a9 on this shaft, coinpressing the fiber washer 56 between the fixed metal washer 53 and the rotatable metal washer 57. A follower or nut- 62 is provided on the screw threaded sleeve 4-.6, this follower being preferably stamped from sheet metal and having an outwardly ext nding portion ,3 with an opening 64 therein. The follower is shaped to loosely the threads on the sleeve l6. A stop for the follower 62 is provided at the'lower end of the sleeve 46 by the upturned extension 65 of a washer 66, this washer being pressed, riveted or otherwise suitably secured to the lower end of the sleeve 46 as shown. A key 67, frictionally retained n a hole 68 through the dish 45 acts as stop for the follower G2 at the upper end of the sleeve 46. As shown in Figs. 2 and 3, the upwardly extending arm 58 on the washer 5? passes through the opening 64 in the follower 62.

In operation, when a torque is produced in the rotor cup ii by alternatlng currents in the e c winding 0 tr e r wu the fi ll 1 he cup l4 tog the th L disk -15 and its integral sleeve l6 rotate freely, running the follower 62 up or down the sleeve -6 on the threads thereon, the shaft 2 remain- COllSlt'lQ now the operation of the relay as a whole, when the relay has run to the end of it stroke, moving the contacts 21 and nent throi 'h the pinion 4-, o, tne shaft and the arm 17, one s gs 36 of the centering de ice compressed. the

cquired by the rotor ing absorbed by the s washer between the iibe' w e The initial movement of the inn its neutral position is oppose ,ugly by the inturned end 32 t rm described above.

d i "3 eng i es the angularlv 1 in urned portion 32, move. rapidly to its 3 and 3 are de-energiz cod in the rotor l-l a of the centering eevice O f r 6, together with the contacts a toward the neutral position.

6 reaches the neutral position, or I the inturned end 3t wit 6 is broughtto ion. As the shaft device C, the sha 5i g 2 i e i lalf) aequir c momentum, bein I" 5 and the pinion 41- f the shafts b and 2 a' device C in their n we rotor cup 4hr, together i} .o the sleeve 46, continue t. rotate due to the momentum acquired by ho rts, the follower 62 being moved in ll. The

follmver 62 and the threads are so arranged that the rotor T e the follower travels from one end o threaxils to the other, and in this manner the .anoinentum acquired by the rotor cup 4A and the disk 45 is dissipated in friction during this free rotation thereof after the shafts 2 and 6 have come to a stop. This means for dissipating the momentum acquired by the rotor structure prevents this momentum from tending to carry the shafts 2 and 6 beyond the neutral position and thereby causing the undesirable opening and closing or bobbing of the relay contacts referred to above. It will be noted that when the relay is again energized to close its contacts, the follower 62 is ordinarily located at some intermediate point on the sleeve 46, and for this reason the rotor cup 44 together with the disk 45 and the sleeve 46 is rotated freely by the torque produced by the field windings until the follower 63 engages one or the other of its stops 65 or 67 when the shaft 2 is rotated by the cup 44. This initial free run of the rotor cup 44 permits the freely moving parts to acquire a considerable velocity and momentum which serves to overcome the initial opposition afforded by the centering device C as described above.

Although the present invention has been described in a rather specific manner and in connection with certain specific details of construction, it should be clearly understood that the invention is not limited in its scope to the disclosure, except as indicated in the appended claims. For instance, any number of contacts may be provided on the shaft 18, and these contacts may be arranged to engage or to disengage their corresponding stationary contacts in either of the energized or in the de-energized position of the relay as desired.

What it is desired to secure by Letters Patent is 1. In a relay mechanism, a movable contact element having two operated positions,

an electrically driven element mechanically connected to said contact element through a lost motion connection including a screw threaded traveler, and adapted to move said contact element to one of said operated positions, a mechanical centering device connected to said contact element, said centering device including means for moving said contact element to the other of said operated positions and means for holding said contact element in said other operated position.

2. In a relay mechanism, a contact element having a plurality of operated positions, a

biased device including initially tensioned isaid contact element to its other operated positions, said driving device being connected to a lost motion element engaging a member yieldably connected to means for driving said contact element through said yieldably connected member.

3. In an alternating current relay, a movable contact element adapted to control electrical circuits and having a neutral and an energized position, an electro-magnetically operated rotor connected to operate said contact element from said neutral position to said energized position, a mechanical centering device for moving said contact element and said rotor from said energized position to said neutral position, said centering device having a structural configuration for strongly opposing only the initial motion of said contact element from the neutral position to the energized position, and means for permitting the dissipation of the momentum acquired by said rotor when driven by said centering device comprising a lost motion connection including a threaded traveler member between said rotor and said centering device.

4. In an alternating current relay of the induction type, a movable contact element, a rotor element carried by a shaft mechanically connected to said contact element, means for driving said rotor element by electro-magnetic induction whereby said rotor element may move said contact element in one direction, and a driving connection between said rotor element and said shaft comprising a friction member cooperating with a threaded traveller.

A relay comprising a movable contact element having a neutral position and an energized position, an electrically operated driving element mechanically connected to said contact element and adapted to move said contact element to said energized position, a mechanical centering device for moving said contact element and said driving element to said neutral position, and a yieldable lost motion connection between said driving element and said movable contact element including a friction member and a traveller arranged to move relatively to said friction member in a longitudinal direction, and restrained from relative movement in a direction transverse to said friction member.

6. In a relay mechanism, a contact element having a neutral position and an energized position, a shaft mechanically connected to said contact element, an electro-magnetical- 1y operable rotor mounted to turn on said shaft and having a screw threaded portion integral therewith, a yieldable lost motion connection between said rotor and said shaft comprising a nut engaging said screw threaded portion and adapted to move between stops on said portion and a Washer yieldably connected to said shaft and having an extension engaging said nut, said rotor being adapted to move said contact element to said energized position through said yieldable lost motion connection, and a centering device mechanically connected to said contact element for moving said element to said neutral position.

7. In an induction type relay, a m=- contact element having a neutral position and an energized position, a shaft mechanically connected to said contact element, an electromagnetically operable rotor mechanically connected to said shaft and adapted to move said ft and said contact element to said energized position, a radially extending member fixed to said shaft, a biased arm having a hook-like engagement with said radially extending member when said shaft is in said neutral position, and a direct engagement with said member when said shaft is in said energized position, said biased arm acting to move said contact element to said neutral position, and a yieldable lost motion connection between said rotor and said shaft.

8. In an induction type relay, a movable contact element having neutral position and two energized positions, a shalt mechanically connected to said contact element, an electromagnetically operable rotor connected to said shaft and adapted to move said contact element and said shaft to either of s id energized positions, two radially extending members rigidly connected to said shaft, two hook ended pivotally mounted arms engaging said members in said hooks at times only and biased to move said shaft and said contact element through said respective members to said neutral position from either of said energized positions, and drive means including a lost motion connection and friction clutch between said rotor mechanism and said shaft whereby the momentum acquired by said rotor when driven by said biased arms may be dissipated in friction after said shaft and said contact element have been moved to said neutral position.

9. In an induction relay, a movable contact element having a neutral position and two energized positions, a shaft mechanically connected to said cont-act elements, an electromagnetically operable rotor connected to said shaft and adapted to move said contact element and said shaft to either of said energized positions, two radially extending members rigidly connected to said shaft, two pivotally mounted arms engaging said members and biased to move said shaft and said contact element through said respective members to said neutral position from either of said energized positions, said arms having extending means at their free ends whereby the initial movement of said members and said shaft from said neutral position is more strongly opposed than the subsequent movement toward one of said energized positions. and a lost motion connection between said rotor mechanism and said shaft whereby the momentum acquired by said rotor when driven by said biased arms may be dissipated in friction after said shaft and said contact element have been moved to said neutral position.

l0. 2-, relay comprising a movable contact element having a neutral position and two energized positions, an electrically operable driving means connected to said contact element and adapted to move said element to either of said energized positions, a mechanical center ng devic for moving said contact element from either of said energized positions to said neutral position, and a yieldable lost motion connection between said driving means and said centering device including a threaded traveller associated with frictionally held driving member for said contact element.

11. In an alternating current relay, a movable contact element adapted to control electrical circuits and having a neutral and an energized position, an electromagnetically operated rotor connected to operate said con tact element from said neutral position to said energized position, amechanical center ing device for moving said contact element and said rotor from said energized position to said neutral position, said centering device having a structi 'al configuration for strongly opposing on the initial motion of said contact element from the neutral po sition to the energized position, and means for permitting the dissipation of the momentum acquired by said ro when driven by said centering device comprising lost motion connection including a threaded travel-- ing member between said rotor and said cen tering device, and friction means associated with said movable contact element and arranged to be driven by the traveling member upon the latter reaching the end of its travel.

12. In a relay mechanism, a contact element having a neutral position and an energized position, a shaft mechanically connected to said contact element, an electro-mag netically operable rotor mounted to turn on said shaft and having a screw threaded portion integral therewith, a yieldable lost 1notion connection between said rotor and said shaft comprising a nut engaging said screw threaded portion and adapted to move between stops on said portion and a washer yieldably connected to said shaft and having an extension engaging said of, said rotor being adapted to move said contact element to said energized position through said yieldable lost motion connection, and centering means comprising, a radially extending member fixed to said shaft, a biased arm having a hook-like engagement with said radially extending member when said shaft is in said neutral position. and a direct engagement with said member when said shaft is in said energized position, said biased arm acting to move said contact element to said neutral position.

13. In a relay, a contact element movable to an energized and a neutral position, drive means for moving the contact element to en ergized position, and a centering device for moving said contact element to neutral position and including an arm fixed to the contact element, a biased pivoted arm with an inturned hook shaped end engageable at times with said arm in the bend of its hook, and at times with the end of the hook, to thus vary the biasing eflect on said contact element.

14. In a relay, a contact element movable to an energized and a neutral position, drive means for moving the contact element to energized position, and a centering device for moving said contact element to neutral position and including an arm fixed to the contact element, a biased pivoted arm with an inturned hook shaped end engageable at times with said arm in the bend of its hook, and at times with the end of the hook, to thus vary the biasing effect on said con tact element, said drive means including, a threaded traveller, stop means for limiting movement of the traveller, and a friction member engaged by the traveller and movable thereby when the traveller is against said stop means.

In testimony whereof I hereby aflix my signature.

RICHARD C. LEAKE. 

